SEOTLION IT. 
CRETACEOUS GASTEROPODA OF THE MIDDLE MARL BEDS OF NEW 
JERSEY. 
MURICID. 
Genus PERISSOLAX Gabb. 
PERISSOLAX TRIVOLVA. 
Plate xx1, Figs. 1-3. 
Fusus trivoluus Gabb: Proc. Acad. Nat. Sci., Phila., 1860, p. 94. 
Perrissolax trivolua Gabb: Synopsis, p. 67; Meek, Check List Cret. and Jur. 
Foss., p. 23; Geol. N. J., Newark, 1868, p. 730. 
Shell of medium size, ventricose, with a long, straight canal, once 
and a half as long as the length of the inner part of the body whorl 
above it. Spire very low, broad, conical; the apical angle being from 100° 
to 110°, the top of the volutions flattened in the direction of the slope of 
the spire, and the inner volutions barely rising above the outer ones. Body 
whorl flattened on the periphery, forming a nearly vertical, flattened band 
of considerable depth, below which a second obliquely flattened space of 
somewhat less width occurs, thus forming the three angles on the body of 
the whorl from which the name was derived. Below the lower angle 
the surface slopes rapidly to the long, slender canal and beak. Aperture 
large, angular on the outside and contracted below at the canal, strongly 
modified on the inner margin by the preceding volution. Volutions faintly 
marked by distant varices and along the upper carina by a series of thin, 
rather closely arranged transverse nodes. No fine surface markings or 
spiral lines are perceptible on any of the specimens, all of which are internal 
casts ina rather coarse yellow lime sand. 
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